Listservs connect professionals who share interest in a particular field or topic. Subscribed members receive updates by email.
Listservs can be a great way to learn more about or get involved with your area(s) of interest. Some organizations have members-only listservs, but many other listservs are open and free for all to join.
You don't necessarily have to feel ready to actively contribute to the discussions; just "lurk" to begin with to start learning from other scholars around the world.